perf scripts python: exported-sql-viewer.py: Add context menu

Add a context menu (right-click) that provides options for copying to
clipboard, including, for trees, the ability to copy only the cell under
the mouse pointer.

Committer testing:

$ python ~acme/libexec/perf-core/scripts/python/exported-sql-viewer.py ~/c/adrian.hunter/simple-retpoline.db

Simply right click and pick "Copy selection", that at this point has
just the first line, not expanded, then see what was copied by pressing
shift+control+v on a terminal:

Call Path,Object,Count,Time (ns),Time (%),Branch Count,Branch Count (%)
▶ simple-retpolin,,,,,,

Ditto after expanding, i.e. the selection continues to be just one
line:

Call Path Object Count Time (ns) Time (%) Branch Count Branch Count (%)
▼ simple-retpolin

Now select all the lines with the mouse and control+shift+v again:

Call Path Object Count Time (ns) Time (%) Branch Count Branch Count (%)
▼ 14503:14503
▼ _start ld-2.28.so 1 156267 100.0 10602 100.0
▶ unknown unknown 1 2276 1.5 1 0.0
▶ _dl_start ld-2.28.so 1 137047 87.7 10088 95.2
▶ _dl_init ld-2.28.so 1 9142 5.9 326 3.1
▼ _start simple-retpoline 1 7457 4.8 182 1.7
▶ unknown unknown 1 805 10.8 1 0.5
▶ __libc_start_main libc-2.28.so 1 6347 85.1 179 98.4

Signed-off-by: Adrian Hunter <[e-mail]>
Tested-by: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/scripts/python/exported-sql-viewer.py

···
 		self.view.setSelectionMode(QAbstractItemView.ContiguousSelection)
 		self.view.CopyCellsToClipboard = CopyTreeCellsToClipboard
 
+		self.context_menu = TreeContextMenu(self.view)
+
 	def DisplayFound(self, ids):
 		if not len(ids):
 			return False
···
 		self.view.setModel(self.model)
 
 		self.ResizeColumnsToContents()
+
+		self.context_menu = TreeContextMenu(self.view)
 
 		self.find_bar = FindBar(self, self, True)
 
···
 def CopyCellsToClipboardCSV(view):
 	CopyCellsToClipboard(view, True, True)
 
+# Context menu
+
+class ContextMenu(object):
+
+	def __init__(self, view):
+		self.view = view
+		self.view.setContextMenuPolicy(Qt.CustomContextMenu)
+		self.view.customContextMenuRequested.connect(self.ShowContextMenu)
+
+	def ShowContextMenu(self, pos):
+		menu = QMenu(self.view)
+		self.AddActions(menu)
+		menu.exec_(self.view.mapToGlobal(pos))
+
+	def AddCopy(self, menu):
+		menu.addAction(CreateAction("&Copy selection", "Copy to clipboard", lambda: CopyCellsToClipboardHdr(self.view), self.view))
+		menu.addAction(CreateAction("Copy selection as CS&V", "Copy to clipboard as CSV", lambda: CopyCellsToClipboardCSV(self.view), self.view))
+
+	def AddActions(self, menu):
+		self.AddCopy(menu)
+
+class TreeContextMenu(ContextMenu):
+
+	def __init__(self, view):
+		super(TreeContextMenu, self).__init__(view)
+
+	def AddActions(self, menu):
+		i = self.view.currentIndex()
+		text = str(i.data()).strip()
+		if len(text):
+			menu.addAction(CreateAction('Copy "' + text + '"', "Copy to clipboard", lambda: QApplication.clipboard().setText(text), self.view))
+		self.AddCopy(menu)
+
 # Table window
 
 class TableWindow(QMdiSubWindow, ResizeColumnsToContentsBase):
···
 		self.view.CopyCellsToClipboard = CopyTableCellsToClipboard
 
 		self.ResizeColumnsToContents()
+
+		self.context_menu = ContextMenu(self.view)
 
 		self.find_bar = FindBar(self, self, True)
 
···
 		self.view.verticalHeader().setVisible(False)
 		self.view.setSelectionMode(QAbstractItemView.ContiguousSelection)
 		self.view.CopyCellsToClipboard = CopyTableCellsToClipboard
+
+		self.context_menu = ContextMenu(self.view)
 
 		self.ResizeColumnsToContents()